347 Stainless Steel Bar - AMS 5646

Available Diameters in Inches
.3125" - 6.00"
Available Diameters in Millimeters
7.938 - 152.400
  • 347, 347 round bar, pwa lcs
    347 Stainless Steel Bar - AMS 5646 - Color Code Plum Purple


  • Alloy 347 stainless bar is a columbium and tantalum stabilized austenitic chromium-nickel stainless steel and was developed to provide an 18-8 type alloy with improved intergranular-corrosion resistance. This grade is stabilized against chromium carbide formation by the addition of columbium and tantalum. Since columbium and tantalum have a stronger affinity for carbon than chromium, columbium-tantalum carbides precipitate within the grains instead of forming at the grain boundaries. Alloy 347 stainless bar should be considered for applications requiring intermittent heating between 800ºF (427ºC) and 1650ºF (899ºC), or for welding under conditions which prevent a post-weld anneal.

Nominal Composition

  • Iron - 68%
  • Chromium - 18%
  • Nickel - 11%
  • Columbium+Tantalum - 10 x Carbon minimum

Standard Inventory Specifications

  • AMS 5646
  • ASTM A 193
  • ASTM A 276
  • ASTM A 479
  • ASTM A 269
  • ASME SA 240
  • QQ S 763
  • UNS 34709
  • UNS S34700
  • Line marked >.500 inch diameter
  • Predominantly produced by AOD process. Annealed, centerless ground or rough turned.
  • DFARS complaint

Standard Inventory Lengths: 10-12 feet rl's

Common Trade Names

  • 347 stainless, alloy 347. 347

Industry Applications

  • Aerospace
  • Chemical Processing
  • Oil & Gas


  • Non-magnetic. The corrosion resistance of this grade is similar to Type 304 stainless steel. Alloy 347 stainless steel round bar is used for welded equipment which cannot be annealed and for equipment which is operated between 800-1500˚F (427-816˚C). The elevated temperature stress rupture and creep strength of ths grade are higher than Type 304 stainless steel. The room temperature yield strength and tensile strength are approximately 35,000 psi and 85,000 psi, respectively.


  • The hardness of Aerodyne Alloys stock is typically 170 BHN and is supplied in the fully annealed condition. Alloy 347 stainless steel round bar is not hardenable through heat treatment, but small sections can be cold work hardened. Room temperature yield strength is typically 40,000 psi with tensile strength of 90,000 psi.


  • Rating: 80% of B-1112
  • Typical stock removal rate: 90 surface feet/minute with high speed tools.


  • 347 stainless machines with tough and stringy chips and has a high rate of work hardening and requires a rigid set-up, plenty of power and positive cuts. Use as heavy a cut as possible to prevent surface work hardening and glazing.

Density: 0.290 lbs/in3, 8.03 g/cm3